Existing mouthguards are generally horseshoe or U-shaped, with inner and outer walls that form a trough or channel for the upper or lower teeth. The mouthguards are typically made of a type of resin, usually a thermoplastic that softens in boiling water allowing the user to customize the mouthguard to fit the user's mouth, while still maintaining shock absorbing properties. The mouthguards are generally produced using an injection molding process, during which the resin is injected at high pressure into a mold, which is the inverse of the product's shape. The mold is typically made from metal and precision-machined to form the features of the desired part. In the molding process, the design of the mold must account for the ability to remove the molded product from the mold without damaging or distorting the molded product.
As many mouthguards are worn in team sports, it would be advantageous to have mouthguards that colored with the appropriate team colors. During the manufacturing process, a colorant, such as dye, can be added after the resin to produce different colors for the separate pieces that are injection molded.
This form of color customization has some major disadvantages with regards to the production and mass manufacturing of the product. Each time the colorant is added, the entire injection molding process is lengthened, which in turn increases production costs. In addition, because a different colorant has to be used if different colored pieces are desired, the process is further lengthened, and a continuous process cannot be maintained. Since the colorization of the mouthguard must be done during the manufacturing process, any commercial mass manufacturer must accurately predict the amount of mouthguard that will sell for each color and make the right amount for each. Such a prediction is not practical. Any pre-colored mouthguards that have the wrong team colors will not be bought by the users.